This invention rlates to a method of splicing spun yarns, and more particularly to a spun yarn splicing method wherein ends of both yarns positioned in overlapping relationship within a yarn splicing hole are acted upon by a compressed fluid to effect an intended splicing of yarns.
Conventionally, well known as a method of splicing spinning yarns is one wherein either a fisherman's knot or a weaver's knot is formed in order to knot yarns to each other. Such methods are useful for mass production where mechanized, but have a significant defect that a knot formed by knotting of yarns has a thickness of up to three times of that of a single yarn. This results in a disadvantage that yarn breakage is likely to occur to yarns during weaving with such yarns, and a knot will be involved in a woven fabric of a final product, thus necessitating an additional process to remove a portion of the woven fabric around such a knot as a defect of the fabric, to push in such a knot behind the reverse side of the product, or the like.
As a means for removing such defects as described above, there have been proposed another yarn splicing method and device which can provide a completely different joint and structure than a fisherman's knot, a weaver's knot, and so on. In particular, according to this method, portions of ends of yarns which are overlapped one on the other are acted upon by a compressed fluid so that they are intermixed with each other and fibers thereof are interlaced with each other.
So far, there have been proposed various yarn splicing methods which employ such a pneumatic means as described above. Typically, a Japanese Publication Patent No. 56-47108 discloses a method wherein yarn ends are untwisted within nozzle pipes before they are spliced, and then when the yarn ends are to be spliced, in a condition in which an extremity of each of the yarn ends is sucked and held by means of a suction air flow while the other side is held fixed, the yarns put in order in overlapping relationship within a yarn splicing hole are acted upon by a flow of compressed air.
In this method, in case a spinning yarn of low expansibility is used, yarn ends cut off can be sucked into yarn end controlling nozzle pipes disposed adjacent a yarn cutting device without any trouble. However, in case yarns to be spliced are core spun yarns having a core of an elastic polyurethane material and a spun yarn twisted around the core, at the instant when yarns are cut, ends of the yarns thus cut off are released from grasped condition and there appears a sudden contraction of the yarn ends due to the elastic force thereof, which will cause the yarn ends to leap over openings of the yarn end controlling nozzle pipes, preventing the yarn from being sucked into the yarn end controlling nozzle pipes, resulting in error. Consequently, intended splicing of yarns may not be effected in error, and even if yarns are spliced, a joint obtained will be of a low strength and thus become an extremely unsatisfactory one.